Thursday, January 28, 2010

Contamination of Groundwater

Though it is was widely believed in the past that groundwater was protected from contamination, this is not true. Obvious contamination sources, such as landfills, lagoons, and other waste facilities are easily identified. Sources not so easily recognized as potential contamination sources include agricultural, industrial, and mining operations, and naturally occurring processes such as salt water intrusion. While it is quite common to dispose of waste by burying it, in doing so, we have at times opened the route of contamination for ground water. Once buried, some wastes are forgotten and become more difficult to locate as time passes. Waste disposed of in surface dumps also poses a threat, especially when rainwater or snowmelt seeps down through it into the groundwater. Because groundwater in many geologic formations moves slowly, a contamination problem can remain undiscovered for years or decades before the contamination plume reaches a well (or other outlet) where it is discovered. Fractured rock formations which tend to be groundwater rich in places like Virginia, are particularly susceptible to groundwater contamination. Public water supplies are routinely tested; however, private wells are only tested at the discretion of the owner. (Though the department of health recommends regular testing of private drinking wells, it is not required. In addition, when home owners test their drinking water they routinely only test for coliform- bacterial contamination.)

Remediating groundwater contamination is difficult and expensive. Often, treatment of contaminated groundwater is also expensive. The best approach is to prevent the contamination of groundwater. There is not a comprehensive estimate of ground water contamination costs for Virginia. An example of the magnitude of costs associated with groundwater contamination can be obtained from a review of the underground storage tank program. Between 1990 and 1998 the Virginia Department of Environmental Quality reimbursed tank owners $67 million for remediation of ground water contamination. These reimbursement costs do not include the costs borne by the tank owners or costs associated with remediation activities where responsible parties could not be identified. Gasoline floats on groundwater and is only somewhat soluble, it is introduced as a point source of contamination and thus, it is relatively easy to capture and clean up. The costs associated with other types and sources of contamination would be enormous.

Sources of groundwater contamination

Leaks and spills of petroleum products. Contamination of groundwater by petroleum products from leaking fuel tanks (both heating oil and gas and diesel fuel tanks), pipelines, and spills and releases. After World War II it became common practice to bury fuel tanks in the ground. No one thought about what would happen over time when these tanks rusted and began to leak creating a slow and steady source of contamination. In the late 1980’s the states began to regulate underground storage tanks, USTs. Virginia began a program to register, regulate and cleanup USTs and their contamination in 1989 and has spent over $67 million in the effort to cleanup contamination from USTs. As the backlog of historic contamination is cleaned up and the more protective regulations reduce the future contamination, USTs are becoming a smaller threat in the future. Motor oil can also pose a threat to groundwater. It is estimated that over 4 million gallons of used oil are disposed of improperly by do it yourself oil changer in Virginia each year. Improper disposal especially pouring it out on the ground or sending it with household waste to the sanitary landfill can impact groundwater.

Military installations have historically used solvents as degreasing agents for machinery and equipment, disposed of waste on site, have had underground pipelines associated with fueling operations, and fuels storage systems. These have often been large quantity operations and can result in significant impact to groundwater especially where the aquifer is unconfined.

A landfill is a site where trash and garbage are disposed of. Historically, mixed waste was simply buried and this resulted in contaminated leachate impacting groundwater. Leachate is the liquid formed when rainwater and snowmelt filter or percolate through buried refuse. The liquid formed by dissolving waste is the leachate. If the leachate is not captured and treated it can contaminate groundwater. Many of the old hazardous waste disposal sites have turned into CERCLA (Superfund) sites. Currently there are 26 federal NPL sites in Virginia including the 2008 Sterling CERCLA site. It is reported that a quarter of CERCLA sites are old landfills.

Under the federal Resource Conservation and Recovery Act (RCRA) definitions and regulations were created for sanitary landfills, a site where sold waste is disposed on land without creating public health or safety hazards. Landfills now required a clay or synthetic liner, and the compacted waste must be caped at the end of each day with soil, monitoring wells to check for groundwater contamination are required for active and closed sanitary landfills. These days, landfills usually contain household waste. Each person in the US creates and average of 4.5 pound of trash daily. It is important that hazardous materials are not disposed of with the regular household trash, and are instead properly recycled.

Onsite Sewage Disposal Systems
Cesspools, which directly disposed of untreated sewage wastewater into pits, are no longer permitted in Virginia. These days only septic and alternative onsite sewage systems (AOSS) are permitted in Virginia. Proper location, density, and maintenance of septic systems is necessary to ensure that the AOSS and soil can absorb wastewater from the system and remove the contaminants and disease causing bacteria before it can impact the groundwater. Home owners must also be careful not to dispose of insecticides, herbicides, solvents, paints, drugs or other chemicals in their sinks and toilets. Septic systems and AOSS are not designed to remove these substances and they will pass directly to the groundwater. Currently, there are Emergency AOSS regulations awaiting the Governor’s signature.

Agricultural activities can cause degradation of the groundwater. Excessive use of fertilizers and pesticides or improper application or disposal of these substances can contaminate groundwater. Shallow groundwater can also be impacted by runoff of pesticides and improper well construction. In addition, improper management, storage and disposal of animal waste from manure piles, animal waste lagoons and feedlots (which are not common in Virginia) can contaminate groundwater with biological contaminates and nitrate. Suburban pesticide use and surface runoff can also have significant impacts on groundwater. Excessive use of herbicides and pesticides on ornamental gardens can contribute to runoff and ground infiltration of pesticides. Injecting termite control chemicals directly into the soil surrounding all houses needs to be rethought and pest control planned and appropriately handled.

In southwestern Virginia coal mining can impact groundwater. Acidic ground water caused by the coal mining can be a serious problem. Below ground mining can intersect a groundwater aquifer and introduce contaminants into the aquifer. Tailing ponds used to dispose of mining waste can be a source of groundwater contamination. Mining is often associated with acidic impacts to groundwater.

Finally, coastal areas can be affected by saltwater intrusion caused by heavy pumping of the groundwater, a decrease in recharge or an increase in sea level. When the artesian layer of groundwater is pumped beyond its recharge rate, saltwater will rush flow in to fill the void. This is a growing problem in the Tidewater region of Virginia. Groundwater levels in the Tidewater region of Virginia’s coastal plain are continuing to decline. Impacts from groundwater withdrawals are propagating along the fall line into the coastal plain and have the potential to interfere with wells in these areas. Given current groundwater declines, the entire coastal plain aquifer system must be managed to maintain a sustainable future supply of ground water.

Monday, January 25, 2010

The Geological Regions of Virginia

Loudoun County’s proposed amendments to the zoning ordinances that would create a Limestone Overlay District (LOD) got me thinking of about the geology of the state. I did not grow up in Virginia, but not only is my husband a native son of the Commonwealth, but he comes from a long line of teachers and I have sweet memories of a road trip with his Aunt Louise amusing her great nephew with teachable moments as we drove through the Valley, to the Blue Ridge, to the Piedmont. It was not until years later that I realized that Aunt Louise had been teaching her five year old great nephew (and me) the geological regions of Virginia.

The geological regions of Virginia are (from east to west) the Coastal Plain, the Piedmont, the Blue Ridge, the Valley and Ridge and the (Cumberland) Plateau. Historically, the geology of these regions has determined what the lands can be used for and by implication the nature of the communities that developed in these regions. Post World War II development of the suburbs had disconnected us from the direct ties to geology, but the density of the population and the demand for water, specifically groundwater is bringing us bank to understanding our geological destiny. The natural occurrence of groundwater depends on the geological conditions.

The Costal Plain of Virginia is composed mostly of unconsolidated geologic deposits and extends from the Atlantic coast to the “fall zone” a geological line that runs north-south through Fairfax, Fredericksburg, Richmond, and Petersburg. At its widest portion the Costal Plain is over 100 miles wide. Costal Plain deposits consist of alternating layers of unconsolidated sand, gravel, silt, shell strata and clay and slopes generally southeast. There are two groundwater systems, an unconfined aquifer and a lower artesian aquifer both flow in the general direction of the topography slope towards the ocean. In the 1990’s it was estimated that approximately half of Virginia’s groundwater use was in this region. The principal recharge area for these aquifers is the land around the fall zone where the aquifers outcrop. There is some leakage from the upper to the lower aquifer, but that is relatively insignificant. The Costal Plain’s artesian aquifer has an enormous groundwater storage capacity and Virginia remains a relatively wet location, but pumping (possibly over pumping) has lowered the artesian pressure allowing some salt water intrusion near the coast and overbuilding in the recharge zone has impacted the availability of water. It is projected with little more population growth that during drought years Fairfax and the Norfolk-Virginia Beach area will have inadequate water.

The Piedmont is bordered by the “fall zone” on the east and the Blue Ridge Mountains on the west. The Piedmont is the largest geological region in Virginia and has a diverse geology largely dominated by igneous and metamorphic rocks, with some areas of sedimentary rocks. The area has limited overburden and the fractures and fault lines formed in the rocks store and transmit groundwater. The size and number of water bearing fractures decrease with depth so significant supplies of water are generally located in the first few hundred feet. There is a wide variation in groundwater quality and yield ranging from under 1 gallon to over 50 gallons a minute. The largest yields are obtained where fracture and fault system are extensive (like my neighborhood) along the base of the Blue Ridge Mountains. In other areas of the Piedmont, disintegration of the granite bedrock forms a zone of granular material with slow recharge and relatively high and annoying amounts of iron and sulfur. The fractures and faults offer a route of transport for any contaminants so that the most water rich areas are the most susceptible to contamination.

The Blue Ridge province lies to the west of the Piedmont and is a narrow zone (4-25 miles wide) of mountains that runs from North Carolina to Maryland with the highest elevations in Virginia. The bedrock is near the surface and relatively impervious and contains limited amounts of water in joints, fractures and fault zones. Igneous and metamorphic rocks are most common on the eastern slope (and into the Piedmont) and sedimentary rocks are common on the western slope. Water yields are low and limited and typically very high in iron.

The Valley and Ridge region is to the west of the Blue Ridge Mountains and is underlain by consolidated sedimentary rocks of limestone, dolomite, shale and conglomerate. Limestone and dolomite occur beneath lowlands, such as the Shenandoah Valley (also within the lowlands between the Potomac and the Catoctin Mountains) these deposits consistently form productive aquifers. Karst features such as sinkholes, caves, and large springs are found in the Valley and Ridge province. The ridges in the upland area are typically underlain by sandstone and shale with limited groundwater yield. Limestone frequently contains underground channels that store and transmit groundwater. Rapid movement of water in the limestone area makes the pollution potential high. Aquifers are often recharged directly by streams crossing fault zones giving wells in these areas the highest yields. This direct surface water to groundwater recharge can create serious water quality problems. The groundwater in these zones bypasses any natural filtration the soil might have provided. The quality of the groundwater would reflect the quality of the seasonal streams and surface water.

The final and smallest geological region of Virginia is the Cumberland Plateau also called the Appalachian Plateau which includes the southwester tip of Virginia. This region is underlain by sedimentary rocks, primarily sandstone, shale and the coal. It is the presence of coal that has most determined the fate of this region. The gentle folding of these formations has created domes and basins and faulting has occurred. Groundwater quality is generally best in the bedrock above the stream level. The groundwater in the stream level contains high concentrations of sulfate, sulfite, nitrate, iron and carbon dioxide. The water improves at 150-300 feet below this area. Groundwater is generally used for small domestic purposes and processing coal. The shallow nature of the groundwater allows for relatively easy contamination.

Virginia is rich in water our actions will determine if we remain so. The process by which water from rainfall, snowmelt, streams and rivers flows into water bearing geologic formation is the groundwater recharge process. The climate change models (as limited and faulty as they may be) predict that Virginia will become a bit wetter and warmer (think North Carolina). A failure of the water supply in Virginia will be due to our own actions and decision. The land surface through which groundwater is recharged must remain open and uncontaminated to maintain the quality and quantity of groundwater of the Commonwealth of Virginia.

Thursday, January 21, 2010

Commonwealth of Virginia HB 332 Alternative Onsite Sewage Systems-Improving the Emergency AOSS Regulations

On October 28, 2009 the Virginia Department of Health published their long awaited and needed Emergency Alternative Onsite Septic System, AOSS, regulations after public comment. The purpose of these regulations is to ensure that these more effective treatment systems are designed and installed appropriately and maintained in a manner to allow them to function properly to be protective of the environment and public health.

For single family homes the new Emergency AOSS regulations require that these tested and approved systems are installed with conservative horizontal set backs, are operated and maintained by a licensed operator, grab samples taken by a licensed operator every five years (and analyzed by an EPA certified laboratory), and an operating manual and records need to be maintained on site.

HB 332 maintains the essential point of the regulations that these effective AOSS are maintained in a manner that makes them function properly for the protection of the environment and public health. However, this bill prevents the Department of Health from requiring routine sampling and analysis of single family AOSS with flows of less than 1,000 gallons a day. The sampling required under the Emergency Regulations was without technical merit or standard protocol. The sampling was statistically invalid, and potentially counter productive to the safety of the system. Developing an effective sampling protocol is impossible because the end of treatment for many AOSS systems is below ground surface and above groundwater. A monitoring well would remain dry and incapable of being sampled. Even if there were a way to sample the effluent at the end of treatment, testing of a septic system operation at a single point in time every five years can be impacted by volume, load, temperature and humidity and is not representative of overall performance. Results from a single test taken every five years can be expected normally to vary from acceptable overall average results and so are statistically misleading and not representative of sound sampling methods.

HB 332 also creates a provision in the law allowing for a homeowner to become trained to operate their own system. This would minimize the burden on many homeowners who are currently fully capable of operating and maintaining their systems or who can be trained to do so and is more in keeping with Virginia’s history and traditions of individual responsibility and self-reliance. Self regulation is a proven and effective model that can work here. Also, HB 332 would allow all Professional Engineers, registered environmental health specialists/sanitarians, authorized onsite soil evaluator or wastewater works operators licensed in the Commonwealth of Virginia to operate and maintain their own single family AOSS without further training.

Finally, HB 332 requires all field technicians working for a licensed operator to be trained to an adequate level to properly maintain the AOSS. This is to prevent licensed operators from hiring untrained and unqualified workers to respond to mandated demand and creates a minimum level of knowledge necessary for anyone working on an AOSS to ensure that these systems are maintained according to manufacturers’ guidelines.

Monday, January 18, 2010

Commonwealth of Virginia HB 332 Alternative Onsite Sewage Systems; Routine Testing-Looking for Support

A new bill HB 332 Alternative onsite sewage systems; routine testing is being carried by Delegate Bob Marshall and is looking for support please contact your Virginia State General Assembly Delegate and Senator and urge them to support and or co-patron it. The bill is currently in House Health, Welfare and Institutions Committee. Let’s work together to get this change done to improve the Alternative Onsite Sewer System regulations. The summary of the bill is below, but the full text can be accessed at the Virginia General Assembly site.
Alternative onsite sewage systems; routine testing; who may test. Prohibits the Department of Health from requiring that owners of alternative onsite sewer systems with flows of less than or equal to 1,000 gallons per day and serving a single-family dwelling provide analyzed samples of effluent on a routine and recurring basis. The Board for Waterworks and Wastewater Works Operators and Onsite Sewage System Professionals must develop licensure for (i) employees or agents of licensed operators and (ii) owner-operators of an individual single-family dwelling that have demonstrated the competence and knowledge to operate, monitor, and maintain their own alternative onsite sewage system. Any professional engineer with a current license in the Commonwealth may elect to be deemed an owner-operator without the demonstration of further competence.
On October 28, 2009 the Virginia Department of Health published their Emergency Alternative Onsite Septic System, AOSS, regulations after public comment. The purpose of the regulations is to ensure that these more effective treatment systems are designed and installed appropriately and maintained in a manner to allow them to function properly to be protective of the environment and public health. The US EPA states in the “Volunteer National Guidelines for Management of Onsite and Clustered Treatment Systems” that improper design, construction, installation, operation and/or maintenance are the source of onsite waste treatment failures. The EPA estimates that 29-30% of Virginia households have septic systems and that 8% of theses systems are AOSS.
For single family homes the new Emergency AOSS regulations require that these systems are installed with conservative horizontal set backs, are operated and maintained by a licensed operator, grab samples taken by a licensed operator every five years (and analyzed by an EPA certified laboratory), and an operating manual and records need to be maintained on site. The HB 332 maintains the essential point of the regulations that these effective AOSS are maintained in a manner that makes them function properly for the protection of the environment and public health. However, the bill prevents the Department of Health from requiring routine sampling and analysis of single family AOSS with flows of less than 1,000 gallons a day. The sampling required under the Emergency Regulations was without technical merit or standard protocol. Developing an effective sampling protocol is impossible because the end of treatment for many AOSS systems is below ground surface and above groundwater. A monitoring well would remain dry and incapable of being sampled. Even if there were a way to sample the effluent at the end of treatment, testing of a septic system operation at a single point in time can be impacted by volume, load, temperature and humidity and is not representative of overall performance. Results from a single test can be expected normally to vary from acceptable overall average results and so are statistically misleading and not representative of sound sampling methods.
The bill also creates a provision in the law allowing for a homeowner to become trained to operate their own system. This would minimize the burden on many homeowners who are currently fully capable of operating and maintaining their systems or who can be trained to do so and is more in keeping with Virginia’s history and traditions of individual responsibility and self-reliance. Self regulation is a proven and effective model that can work here. Also, HB 332 would allow all Professional Engineers licensed in the Commonwealth of Virginia to operate and maintain their own single family AOSS without further training. Finally, the bill requires all field technicians working for as licensed operator to be trained to an adequate level to properly maintain the AOSS. This is to prevent licensed operators from hiring untrained and unqualified workers to respond to mandated demand and creates a level of knowledge necessary for anyone working on an AOSS.

Thursday, January 14, 2010

Reducing My Energy Consumption

I have been systematically making small changes to my home to reduce my energy consumption. I started with the easiest steps; lowering the thermostat in the winter and raising the temperature in summer, purchasing energy star eligible appliances and choosing an LCD TV over a plasma (an LED TV is even more energy efficient, but was not available at the time). The next simple step was to change all the incandescent light bulbs for florescent bulbs and when I installed additional lighting it was florescent fixtures. (Though, I warn that the clothes in my closet look oddly colored in florescent light.) The next project was to install solar films on the windows and patio door and drapes and curtains on all the windows. These were small steps, but I learned over the years that small steps do add up.

The following year, after servicing the heat exchanger and furnace to ensure they were working properly, and appropriately sized for the house, and inspecting the attic and accessible areas of the basement and crawl spaces for adequate insulation, I turned to the Building Envelop Research of the Oak Ridge National Laboratory for guidance. The Oak Ridge National Laboratory performs their Building Envelop Research for the US Department of Energy, DOE. The DOE publishes their guidance in their “Insulation Fact Sheet,” which is available on the blog home page. Following the recommendations by the Oak Ridge National Laboratory the attic, crawl spaces, eves, ductwork, underside of a large portion of the main level floor were insulated with cellulose. The pipes, wall end caps, knee walls, sump pumps and all identified areas were sealed, the garage ceiling was insulated and an insulated garage door installed. I was actually surprised at the winter energy savings and pleased with the improved comfort in the master bedroom and bath.

My next project was to spend the winter saving money eating and entertaining at home, watching DVDs for “nights out” on my LCD, eliminating trips to the mall and saving up money for my next energy saving project. Back in October 2008 President Bush had signed the Emergency Economic Stabilization Act of 2008 (P.L. 110-343). The Act extends the 30% investment tax credit for residential solar Photovoltaic or geothermal heat pump installation for eight years through December 31, 2016 and removed the cap on qualified solar photovoltaic projects and geothermal projects (from the previous $2,000). This allows taxpayers to use the credit to offset dollar for dollar their federal tax liability, and to carry unused credits forward to the next succeeding taxable year. Essentially Uncle Sam was now willing to pay 30% of the cost of my next energy savings project. I couldn’t believe it.
According to the DOE heating and cooling account for 56% of the energy use in a typical U.S. home, making it the largest energy expense for most homes. So that is where I looked for my next project. A wide variety of technologies are available for heating and cooling your home, and they achieve a wide range of efficiencies in converting their energy sources into useful heat or cool air for your home. Heat pump systems provide both heating and cooling and offer the benefit of delivering more useful energy than they consume. Unfortunately, on very hot days or very cold days they do not do as effective a job as an air conditioner and a furnace. For climates with moderate heating and cooling needs, heat pumps offer an energy-efficient alternative to furnaces and air conditioners.

Higher energy efficiencies are achieved with geothermal (ground-source or water-source) heat pumps, which transfer heat between your house and the ground or a nearby water source. Although they cost more to install, geothermal heat pumps have low operating costs because they take advantage of relatively constant ground or water temperatures. However, the installation is expensive because of the need to bury coils to deliver constant temperature fluid or install a groundwater pump and injection well to supply constant temperature water to the system. Ground-source or water-source heat pumps can be used in more extreme climatic conditions than air-source heat pumps, and are more effective at cooling and heating at the extremes.
According to the heating and cooling experts and the manufacturers of the various equipment that I have, my heating and cooling system, which is a split system with a gas furnace and air conditioner for the lower level and an air heat exchanger for the upper level, should last another 7-12 years. The most sustainable approach would be to use the current system for its entire expected life despite the fact that I could probably reduce my energy consumption somewhat by changing from my current equipment to two geothermal (ground source) heat exchangers. Though geothermal heat exchangers are more expensive to purchase and install than a traditional furnace and air conditioner, they are far more efficient, reportedly consuming 25-30% less energy to operate. The most reasonable thing to do was to wait and continue using my current system even with availability of the tax credit. Thought for the next several years I will continue to keep an eye on my equipment condition.

In October 2009 Virginia announced that a portion of the stimulus dollars for the state would be allotted to its Residential and Commercial Solar and Wind Incentive Program to provide rebates to partially reimburse the costs of renewable energy systems. For residential users on the first 10 kilowatts, the rebates will be $2.00 per watt for Photovoltaic Solar systems, $1.50 per watt for small wind turbines and $1.00 per watt for solar thermal units (solar hot water heaters). The rebate is less than you might think because system capacity is defined as the installed system’s predicted peak alternating current (AC) output which is around 75%-80% of the DC rating. Combining this incentive with the federal tax credit of 30% and the sale of the renewable energy credits, REC’s, which can be sold to utilities needing RECs and suddenly, there is a positive return on the investment. It was still a big decision because even with rebates and tax credits we have to come up with the cash to pay for the system and while current prices quoted for RECs are $220-$300 per kilowatt/year and are sold in 4 or 5 year contacts there is no guarantee that the REC’s will have any value in the future.

One of the selection criteria for my home was the large southern roof span, perfect for solar panels. I was able to reserve funds from the Virginia Renewable Energy Rebate Program for a 6 kilowatt solar photovoltaic system before all the money was gone and we put the deposit down for an American made solar photovoltaic system installed by a local company. We will be installing a 6 kilowatt system that we estimate will save us approximately $1,300 per year on our electric bill. That is about twice the savings we achieved by insulating the house; however, the cost (before rebates and incentives) is more than ten times the cost of the insulation project. Even after all the rebates and incentives (assuming I successfully navigate these) this energy savings was many more times more expensive than the insulation project.

Monday, January 11, 2010

Should the Health Department Require the Annual Testing of Private Wells?

Annual testing of private drinking water wells is not required or tracked in Virginia. The Virginia Department of Health recommends that private water supplies be analyzed for total coliform at least once a year, but does not require it. Routine testing of private wells takes place during the underwriting of a mortgage, but at no other time. Undoubtedly, when you purchased your home, the well was tested, but that may have been the last time you bothered to test your well. Owners of private drinking water wells are responsible for their own water quality and should monitor it. This spring I used the WaterCheck with Pesticides to test my water quality. This is a test kit you can either buy and take the sample yourself and ship it off to the laboratory in Michigan or you can have a local laboratory do the sampling to ensure that the local laboratory does a same day analysis for Bacteria (presence/absence for coliform and E. coli) and nitrates. The kits are made by National Testing Labs and can be purchased directly from them or from a variety of distributors.

Over 15 million people in the United States receive their water from private ground water wells. EPA regulations that protect public drinking water systems do not apply to privately owned wells. As a result, owners of private wells are responsible for ensuring that their water is safe from contaminants. According to the U.S. Environmental Protection Agency, septic systems are a major source of contamination of an underground water supply (well or spring). Inappropriate siting of drain fields, and poor design, construction, and maintenance of septic systems, coupled with improper well construction, can lead to contamination of household water. There has been little data collected on frequency and type of private well contamination, but clearly fecal bacteria present in water from the well could indicate contamination from septic or other animal waste. My home is located in an area of horse and cattle farms in an area with very little overburden to protect the aquifer. I keep and eye on my groundwater quality.

There are also vectors of contamination that may result in the introduction of contaminants into a private water supply that do not impact the groundwater supply. Coliform bacteria are commonly found in soil, on vegetation, and in surface water. They also live in the intestines of warm-blooded animals and humans. Some coliform bacteria strains can survive in soil and water for long periods of time. Bacteria washed into the ground by rainfall or snowmelt are usually filtered out as water seeps through the soil, so properly constructed water wells do not typically harbor Coliform bacteria. A well pipe that is improperly grouted or where the grouting has been damaged over time may serve as a vector of contamination of surface runoff.

The test for the presence of coliform bacteria is relatively inexpensive and easy to perform. The standard test is called total coliform and it serves as a proxy for other types of contamination. Water samples that contain any coliform bacteria are generally reported as "total coliform positive" and should be analyzed for fecal coliform or E.coli which test specifically for the bacteria found in the digestive system of humans and animals. These fecal bacteria originate only in human and animal waste. It is unacceptable for fecal bacteria to be present in any concentration in a water supply. Bacteria in water cannot be seen, tasted, or smelled and many health-related symptoms are not immediate. Therefore, the only way to reliably determine if water is contaminated is by a laboratory test. Testing a water supply for a specific disease-causing organism can be expensive. Instead, water supplies are usually tested for the presence of coliform bacteria and only if the water tests positive for coliform is further analysis done.

The Center for Disease Control recommends at a minimum, you should check your well every spring to make sure there are no mechanical problems; test it once each year for total coliform bacteria, nitrates, total dissolved solids, and pH levels. If there is reason to suspect other contaminants, you should test for those as well remembering that analysis is expensive. The Virginia department of Health recommends regular testing of your drinking water well when any of the following conditions apply:
there is an infant in the home;
a new well is constructed;
flooding occurs near the well or spring;
any person or animal becomes sick from a suspected waterborne disease; or
The water supply system on a well or spring has been disassembled for repairs to components such as the well itself, pump, pressure tank, treatment devices or pipe lines.
The question is should the Virginia Department of Health require the testing of private wells annually? If the data from well testing were collected and plotted, areas where the groundwater had be impacted from septic leakage might be identified in a more timely fashion and the conditions of geologically sensitive groundwater could be monitored. The public and private drinking water wells of the state could serve as a proxy to track the health of one of our most valuable resources. Instead of requiring the annual testing of private wells the Department of Health should continue to encourage and recommend the annual testing and collect the plot the data obtained in that way. Data collected over a period of time can be very revealing.

The groundwater basin where my home is located consists of highly fractured rock, and overlain by a thin cover of overburden. The lack of overburden limits natural protection to the aquifer. The sedimentary rocks are highly productive aquifers, but also subject to fractures that allow contaminants to move swiftly and easily through the system and easily reach depth in the groundwater aquifer. There is no natural attenuation in a fractured system. Any malfunctioning septic system, improper disposal, or spill on any property has the potential to impact the drinking water well of other residents to the south, southeast or east. Thus, as a group our neighborhood has decided to test all the private wells every spring and track the data to monitor our aquifer.

Thursday, January 7, 2010

Methane and Global Warming

During the Copenhagen meeting almost unnoticed Robert Watson, the former chair of the Intergovernmental Panel on Climate Change and Mohamed El-Ashry, a senior fellow at the United Nations Foundation along with a group from the scientific and financial communities proposed the creation of a Global Methane Fund. According to this group, targeting methane reduction would be a cost effective and results oriented way to prevent global warming. Methane, one of the "other greenhouse gases," is reportedly responsible for 75% as much warming as carbon dioxide measured over any given 20 years. Unlike carbon dioxide, which remains in the atmosphere for hundreds of years, methane lasts only a decade so reductions in methane release will see climate results within a decade as the total methane in the atmosphere is reduced. According to NOAA, National Oceanic and Atmospheric Administrations, CH4 which absorbs 25 times the heat of CO2 is present in the atmosphere at 1/50 the level of CO2 at 1.8 ppm. Methane levels in the atmosphere have risen for the first time since 1998. This increase was attributed to changes in the permafrost stores of methane.

According to this group if we need to suppress temperature quickly in order to preserve glaciers, reducing methane can make an immediate impact. Compared to the massive requirements necessary to reduce CO2, cutting methane requires only modest investment. This group argues that where they stop methane emissions, cooling follows within a decade, not centuries. Methane amelioration would require non-point source regulation and activity. Methane (CH4) is emitted from a variety of both human-related and natural sources. Methane comes from a variety of sources: landfills, sewage streams, coal mines, oil and gas drilling operations, agricultural wastes, and cattle farms. In the United States, the largest methane emissions come from the decomposition of wastes in landfills, enteric fermentation in ruminant digestion and manure management associated with domestic livestock, natural gas and oil systems, and coal mining. Enteric fermentation occurs when methane (CH4) is produced in the rumen as microbial fermentation takes place. Most of the CH4 byproduct is belched by the animal; however, a small percentage of CH4 is also produced in the large intestine and passed out as gas.

According to the US EPA the largest emitters of Methane in the United States in 2007 was enteric fermentation. I kid you not, belching and (please excuse me) farting animals.

U.S. Methane Emissions by Source (TgCO2 Equivalents)

Source Category 2007
Enteric Fermentation 139.0
Landfills 132.9
Natural Gas Systems 104.7
Coal Mining 57.6
Manure Management 44.0

The Global Methane Fund, does not address the release of methane from the permafrost. In an Opinion piece in the Wall Street Journal Mr. Watson and Mr. Mohamed El-Ashry state “experience has shown that even with modest incentives, methane projects, which are typically small scale, can move fast.” These two gentlemen suggest the creation of a global fund. It won’t work. Methane results from human, animal and plant waste. Landfills are prodigious methane generators and because they are a point source can easily be harvested to produce biogas electricity. The release of methane from the permafrost is not even considered. Though the model for causation is not worked out nor proven, it is argued that un-combusted methane released into the atmosphere is a powerful greenhouse gas and 10% of our nation's impact on the climate comes from the food refuse that ends up decomposing under landfill, and another 10% comes from the gaseous releases of enteric fermentation.

In a New York Times article by Leslie Kaufman, “Greening the Herds: A New Diet to Cap Gas.” Cow that had their grain feed adjusted to include more plants like alfalfa and flaxseed and less corn produce less methane. This feed is more like the natural grasses that the cows evolved eating. The methane output dropped 18-30% depending on the original feed mix while milk production remained stable. In addition to producing less methane, the cows were observed to be healthier. This study evolved out of research performed by the makers of Danon yogurt in France. Scientists working with Groupe Danone had been studying why their cows were healthier and produced more milk in the spring. The answer, the scientists determined, was that spring grasses are high in Omega-3 fatty acids, which may help the cow’s digestive tract operate smoothly.
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Corn and soy, the feed that became dominant feed in the agro-industrial dairy industry, has a completely different type of fatty acid structure. As was carefully chronicled in Michael Pollan’s book “The Omnivore’s Dilemma” during the past 40 years, our agricultural economy as orchestrated by the Department of Agriculture has created a system of fattening cows using an unnatural feed, corn and soy. Cows are healthier and belch less methane if they are feed a diet similar to one they evolved to eat. This should not be surprising and is a small example of unintended consequences of man trying to bend the earth to our will. Our tools to impact and change remain far more powerful than our wisdom to know the right course of action to take with them. We would be far better off if we could restrain ourselves from wide sweeping actions and $100 billion global investment funds and dip our toes in first to see the results. Try to develop wisdom before we try to manage the natural cycles of the earth, and instead follow the earth’s lead. Concentrate our global funds on teaching sustainable farming, sanitation, and providing fresh water .

Monday, January 4, 2010

Loudoun County Virginia Proposed Limestone Overlay District

A large area just east of the Catoctin Mountain range in Loudoun County is comprised of limestone and “Karst terrain” areas. Karst terrain is characteristic of regions that are underlain by limestone and dolomite bedrock. The limestone geology of carbonate deposits in Karst terrain areas is dissolved over time by mildly acidic precipitation, creating fissures. The deposits are highly permeable, allowing surface water to pass through quickly to underlying aquifers and eating away at the limestone. The terrain is also characterized by the presence of certain natural features, such as sinkholes and rock outcrops. In this outcrop area, cavities along vertical joints and sinkholes provide a direct link between the land surface and the water table. Precipitation on the outcrop area tends to infiltrate rapidly into the ground, recharging ground water. However, this land does not have natural protections of the underlying groundwater and just as the cavities are major avenues for ground-water recharge, they also are major route for contaminants to enter and spread throughout the groundwater. Experience in Florida and Texas has shown that Karst terrain is susceptible to subsidence and the creation of sinkholes as well as the easy an wide spread contamination of groundwater. Development on Karst terrain must be carefully managed to protect the property owners.

Uncontrolled development on limestone could result in contamination of groundwater and the drinking water wells that tap into it and significant subsidence and the creation of sink holes that could result in the ruination of property. Loudoun County is attempting to pass amendments to the zoning ordinances that would create a Limestone Overlay District (LOD). There are citizens of the proposed district who are up in arms against this, but also people who support this. The key component of this ordinance is control of future development. The proposed ordinance provides that no preliminary plan of subdivision shall be approved where a well and/or sewage disposal system is to be provided for each building lot in the subdivision, until written approval of proposed locations for such systems has been secured from the Health Director. This is to ensure that the groundwater supply is capable of supporting needs of the eventual inhabitants of the subdivision and the land can support the septic needs of the development without impacting the water supplies of existing residents and creating sinkholes that could endanger their properties. The goal is to make sure we only build what the land can support, that we accept the limits of the earth.

I believe strongly that Loudoun County should control development and abuse of the environment. However, it is essential that the method of control does not turn into a blunt instrument for stopping growth and creating excessive burdens on existing homeowners. Loudoun’s proposed ordinance must contain a time limit for response (or risk turning Virginia into California) say 90 or 120 days. Within that time limit for response, Loudoun must make a decision or the project is presumed to be approved. If the project is rejected, then the county must identify the reasons for the rejection in writing. In addition to the restrictions on new developments is a series of restrictions on existing homeowners that many feel are overly burdensome or misdirected. Loudoun County is actually surprised that homeowners are up in arms at the series of limitations that Loudoun proposes putting on their properties modeled on the Chesapeake Bay Protection Act.

Loudoun County should consider allowing all modifications to existing structures provided that such alteration does not encroach into a Karst/Sensitive Environmental Feature Setback. Limitations on the size of outbuildings (sheds) are not critical to the protection of the overall area. Loudoun County should loosen up on the restrictions to the existing homeowners, however, they should require all homeowners in the area to have their septic systems whether traditional or alternative inspected annually for potential failures and the tanks pumped every three years. Those steps would more directly protect the groundwater from contamination and allow existing homeowners peaceful enjoyment of their property.